The present invention relates to a new and distinct variety of nectarine tree which is hereinafter denominated varietarily as "Crystal Belle" and more particularly to such a nectarine tree which bears an attractively colored semi-freestone fruit which has a firm, white colored flesh, and which is mature for harvesting and shipment in early June. The present variety of nectarine tree is somewhat similar in its date of harvesting with that of the Arctic Glo nectarine tree [U.S. Pat. No. 7,884], which is ripe for harvesting and shipment approximately June 9 under the ecological conditions prevailing in the San Joaquin Valley of Central California, but which is distinguishable therefrom by being ripe for harvesting and shipment as early as June 1 under the same ecological conditions.